Integrated circuits are typically fabricated onto and within semiconductor substrates, with the continuing trend being towards manufacturing ever-smaller devices. Capacitors are one type of component which is commonly used in the fabrication of integrated circuitry, for example in DRAM circuitry. A typical capacitor is comprised of two conductive electrodes separated by a non-conducting dielectric region. As integrated circuitry density has increased, there is a continuing challenge to maintain sufficiently high storage capacitance despite typically decreasing capacitor area. The increase in density of integrated circuitry has typically resulted in a greater reduction in the horizontal dimension of capacitors as compared to the vertical dimension. In many instances, the vertical dimension of capacitors has increased.
One manner of forming capacitors is to initially form an insulative material within which a capacitor storage node electrode is formed. For example, an array of capacitor electrode openings for individual capacitors is typically fabricated in such insulative capacitor electrode-forming material, with a typical insulative electrode-forming material being silicon dioxide doped with one or both of phosphorus and boron. The capacitor electrode openings are typically formed by etching. However, it can be difficult to etch the capacitor electrode openings within the insulative material, particularly where the openings are deep.
One manner of etching openings within dielectric materials, whether capacitor openings, contact openings, or other openings, includes plasma etching. Here, the bombarding species typically comprises electrons which one or both of physically or chemically interact with the dielectric material, typically through mask openings to transfer the pattern of the mask openings into the dielectric material. However in some instances, particularly where the depth of the opening reaches and exceeds twenty times its narrowest width, continued plasma etching can be at a considerably reduced rate, or direct the etching action away from orthogonal to the substrate. Such phenomenon may, in part, be due to the collection of positive ions from the etching species within the lowest point of the openings being etched.
While the invention was motivated in addressing the above identified issues, it is in no way so limited. The invention is only limited by the accompanying claims as literally worded, without interpretative or other limiting reference to the specification, and in accordance with the doctrine of equivalents.